View Full Version : Addressing underhood heat

10-28-2012, 03:57 AM
Working on the power steering leak today the underhood shielding pissed me off. I ripped it all off.

Now, I need to replace it (or some of it). I'm going to be putting some vents and a scoop on (Mafix style & CS scoop). When I cut the scoop hole, I should only cut the skin out, not the bracing correct?

Any suggestions of product to use to replace the underhood shield? I'm thinking of only filling in the spots where the outer skin is exposed (ie. not over the braces).

10-28-2012, 05:44 AM
Alot of my muscle car friends( high HP oldschool v8) use reflective tape on hood (underside) or at least that's what I think it is..

I don't have any thing on my hood and it's been fine.

It may be difficult not to cut some of the bracing out when cutting a hole.....

10-28-2012, 07:53 PM
Alot of my muscle car friends( high HP oldschool v8) use reflective tape on hood (underside) or at least that's what I think it is..


A high quality reflective tape, inexpensive, thin, and perfect for the task.

You want to bring the heat down, get a turbo diaper. Wrap the manifold all the way to the turbo, and the downpipe to the cat, with insulating header wrap.

10-30-2012, 01:10 AM
I'm looking to do a mix.

'Mafix style' vents (but with a CS style instead of ST185).

Along with some reflective heat shield.


10-30-2012, 06:23 PM
There's two different purposes at play there. The reflective material is really just to protect your paint. And living in AZ, I'd say the sun is more damaging than your engine... Many people have removed it (myself included) with no issues to paint whatsoever.

The vents are to reduce the underhood temps overall, which is a good thing. I've wanted to do mine for a while, but have so far hesitated as I don't have a spare hood that I'm comfortable chopping up.

Eric Barrera
10-30-2012, 10:32 PM
Reflective tape works wonders.

I have it on my car and it's noticeably cooler

10-31-2012, 01:31 AM
I dont get how reflective tape can keep under hood temps down. Would that just help keep the heat in, or does it absorb?

The vents along will probably make a world of difference.

10-31-2012, 06:48 PM
It keeps the heat in.

10-31-2012, 06:56 PM
Another question. On the MAfix hood, with the angle of the hood when mounted, arent the vents more likely to work as scoops? Or does the air flow of the car cause more of a suction?

10-31-2012, 11:17 PM
re: reflective tape - Your hood would feel cooler, yes, but your engine temps are unlikely to be affected. The big win is some sort of vent. At some point I will try to fab one myself, but we'll see.

11-01-2012, 01:00 AM
the best option would be a custom hood with a cowl

11-01-2012, 07:38 PM
Reflective tape would just keep heat in, it REFLECTS heat back to the source.

Reflective tape coupled with some sort of venting method would do good. You want to reflect heat away from the hood paint to protect that, but it needs to be swept out some other way.

joe's gt
11-02-2012, 06:31 AM
Vents with a slight lip in the front such as those you see on the stock all-trac hood are ideal. The lip in the front creates a low pressure zone and the high heat, high pressure engine air moves to the lower pressure area through the vents. Air always naturally moves from an area of high pressure to low pressure. Open vents help because air moving across the hood itself creates a low pressure zone, but lips in front of the vents are even more beneficial.